Rotary toothbrush



R. GRIS ROTARY TOOTHBRUSH Filed Nov. 22, 1940 ATTORNEYS Patented Oct. 28, 1941 ao'raar roo'rnnaosn Roberto Gris, Martinez, F. o. c. A., Argentina Application November 22, 1940, Serial No. 366,761

In Argentina November 14, 1940 1 Claim.

The present invention relates to toothbrushes for personal use as distinguished from brushes used by dentists for cleaning the teeth of patients. The latter type of instrument comprises a rotary brush mounted on a handle and operatively connected to the instrument pedestal, or adapted to be connected to the driving mechanism of such pedestal.

The object of the present invention is to provide an improved toothbrush for private personal use, in which the brushing element is of the rotary type, thus allowing the individual to obtain in his home in a simple, easy and efficient manner the same effectiveness in cleaning his4 teeth at the time of his ordinary ablutions as is obtained in the dentists chair.

A further object of the present invention is to provide a toothbrush having a rotary cleansing element mounted on a handle containing a driving mechanism for said cleansing element and means, preferably push-button means, for starting and stopping the rotation of said element.

A further object of the present invention is to provide a rotary toothbrush of the kind described in which the brush element is removably mounted on a shaft extendinglongitudinally within a hollow handle, means being provided on said handle for retracting said shaft from engagement with said brush element to permit removal of said element for cleansing, renewal or sterilization.

A still further object of the present invention -is to provide a rotary toothbrush for individual use, which shall be of compact and simple construction so as to allow of its being used with the same facility as an ordinary toothbrush, and shall be reasonably easy and 'cheap to manufacture and have a low running and maintenance cost.

These and other objects and advantagesv of the present invention will become apparent in the course of the detailed description thereof.

In the drawing:

Fig. 1 is a side elevation of one embodiment oi a rotary toothbrush according'to the present Ainvention.

Fig. 2 is a side view of the brush of Fig.. 1, partly in section and with a portion of the handle removed.

Fig. 3 is a section on the line III- III of Fig. 2, and A Fig. 4 is a section on the line IV-IV of Fig. 2.

In the embodiment of the present invention i1- lustrated in the drawing, brush comprises a handle I made of a suitably rigid material as, for example, a plastic, having a relatively narrow head portion I2 and a wider body portion I4. The head portion I2 has near its free end a rectangular recess I6 adapted partly to accommodate a brush element I8, which, as

the novel rotary toothbest seen in Fig. 2 is mounted on the spliced end 20 of a shaft 22 extending lengthwise of the handle II).` The splined end of shaft 22 terminates in a portion 24 of reduced diameter journalled in a bearing 26 mounted in the nose 28 of the head portion I 2, formed by the recessing thereof. Said shaft isv otherwise supported by an intermediate bearing 30 set in the part of the head portion nearest to the body portion I4, and by an end bearing 32 set in the end of the body portion remote from the head portion.

The head portiony I2 is formed or moulded of a single mass of material and is integral with or rigidly secured to one half `of the body portion, which is longitudinally divided into a main portion I4a and a cover portion 34, adapted to be detachably secured to said main portion as by screws 36 to receive which tapped holes are proiide in said main portion as shown at 38 in Both the cover portion and the main portion of the body portion are hollowed out to form when assembled a chamber 40 extending lengthwise of the handle and adapted to accommodate a driving mechanism 42, a shaft .retracting means indicated generally by the reference numeral 44, and a braking device indicated generally by the reference numeral 46.

The driving mechanism 42 may be a clockwork mechanism, or a small electric motor of a suitable type, but for the purpose of the present description it will be assumed that 'the unit 42 is a clockwork mechanism which is deemed to be sufficiently well known to those skilled in the art not to require further detailed description. It should,

however, be noted that it is preferred that the mechanism 42 be so constructed as to allow the shaft 22 to pass right therethrough and to permit of axial movement of the shaft in response to actuation of the retracting means, without thereby causing any disturbance in the functioning of said driving mechanism.

The driving mechanism 42 is preferably located near the end Vof the body portion remote from the head portion I2, as shown, and the shaft 22 projects beyond said end into and through a winding member 48 to which the shaft is operatively coupled as by a pin 50 fast on the shaft and projecting radially therefrom into a slot 52 Vin the winding member 48, so as to permit of axial displacement ofthe shaft with respect to the winding member, while maintaining the latter in Winding engagement with the shaft. Alternatively, the winding member may be fast on a the shaft, so as to movetherewith upon operation of the retracting means. The free end ol the shaft has secured to it a terminal knob 54.

As previously stated, means are provided for starting and stopping the rotation of the brush I8. When the driving mechanism is an electric motor, a normally open switch included in the energizing circuit of the motor may be provided in the body portion, said switch having associated therewith a push-button projecting outwardly through the body portion. In the embodiment illustrated, however, the starting and stopping means is shown as a braking device 48,

comprising a disc 56 fast on the shaft, normally engaged by a brake pad 58 of suitable friction material mounted on the inside of a hollow member 60 surrounding the disc and urged towards the disc at one point by a spring 62 seated in a. recess 64 of the body portion I4. The hollow member 60 has a centering projection 66 for the spring and a stem 68 projecting through the wall of the body portion and adapted to act as a pushbutton, depression of which will move the member 60 against the action of spring 62 to disengage the brake pad from the disc and thus permit rotation of the shaft 22.

For the purpose of enabling the brush I8 to be removed for cleaning, disinfection or renewal, a retracting means is provided which includes a bell-crank lever 'I6 pivoted at l2 to the body p0rtion and having one arm 'I4 lying substantially flush with the outer surface of said body portion so as to be operable from outside, as in the case of the lever of certain types of self-filling fountain pens. The other arm 'I6 of the bell-crank lever 'I0 terminates in a stirrup 18 located inside chamber 40 into which arm 16 extends through an elongated slot 19 formed in the body portion I4 to allow of free swinging movement of arm 16. The stirrup 'I8 has slotted arms 80, into the slots 82 of which extend pins 84 projecting from a collar 86 slidably mounted on the shaft 22 between stop shoulders 88 fast on said shaft. The operation of this device will be clear to those skilled in the art from inspection of the drawing, and further description thereof is deemed unnecessary. Obviously, other devices having a similar effect may be substituted without departing from the scope of the present invention.

In using the rotary toothbrush of the present invention, the winding member 48 is rotated to wind the mechanism 42, the shaft 22 being turned against the frictional resistance of the brake pad 58 which may, however, be disengaged fromV the disc 56 by depression of the stem 68 during the winding operation. When the toothbrush is fitted with an electric motor, there will, of course, be no winding element such as member 48, and all that is required to prepare the toothbrush for use is to connect the motor circuit to a source of electric energy, which may be the service mains, or a battery either separate or else housed inside the body portion I4. In the latter event, the starting and stopping switch hereinbefore alluded to may be relied on to break the energising circuit when the toothbrush is not in use, or a separate main switch may be provided.

Wiien the spring of the clockwork mechanism 42 has been wound, or the energizing circuit prepared as indicated above, a quantity of toothpaste, powder or other similar preparation is applied to the brush l`8 which is inserted into the mouth, whereupon the stem 68-or the equivalent push-button-may be depressed to start the driving mechanism 42. The brush may be moved while rotating, upwards and downwards, that is, lengthwise, or crosswise of the teeth, whereby a thorough cleansing of the teeth is secured, as the bristles of the rotating brush will readily penetrate into the interstices between the teeth and also scour any corrugations or similar Irregularities. Moreover, the process of cleaning the teeth is rendered less laborious, since the main part of the work is performed by the rotating brush, which need only be gently guided in the lengthwisehand crosswise directions with respect to the teet The fact that the shaft 22 may be retracted to permit removal of the brush, allows of the substitution of the ordinary bristle type of rotary brush by special instrumentalities, such as a massage roller for the gums.

It will likewise be apparent to those skilled in the art, that the novel rotary toothbrush according to the present invention enables the inside faces of the teeth to be eillciently cleaned with much greater facility than when a standard type of toothbrush is used. Furthermore, the novel rotary brush is equally applicable to the cleaning of artificial dentures.

As will be seen from the foregoing, the novel rotary toothbrush of the present invention, is easy to operate, eicient to achieve its purpose, relatively cheap to manufacture, has a low maintenance and operation cost and can be used for a variety of purposes.

It is to be understood that the scope of the present invention is not intended to be limited to the embodiment described by way of example, but that sundry modifications both as to construction and details may be made without departing from the nature of the present invention as defined in the appended claim.

I claim:

In a rotary toothbrush of the kind comprising a handle having a hollow body portion, a shaft extending lengthwise through said body portion and projecting from one end thereof, a brush element detachably mounted on said projecting end and a driving mechanism mounted within said hollow body portion and operatively coupled to said shaft, retracting means for retracting said shaft from engagement with said brush to permit removal thereof, said retracting means comprising a slot in said body portion, a bell-crank lever pivoted at a point on said body portion and having one arm extending through said slot and normally lying substantially flush with the outer surface of said body portion, so as to be operable from without, a second arm extending within said hollow body portion and terminating in a stirrup, said stirrup having a pair of slotted arms extending along opposite sides of said shaft, a pair of spaced stop shoulders fast on the shaft, a collar slidably mounted on said shaft between said stop shoulders, a pair of diametrically opposite pins projecting radially from said collar into the slots in the arms of said stirrup, whereby on movement of said first mentioned arm of the bell. crank lever away from said body portion, said stirrup is caused to bring said collar into contact with the stop remote from said projecting end of the shaft to cause movement of said shaft lengthwise of said body portion and disengagement of said projecting end from said brush. v

ROBERTO GRIS. 

